#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>

int GLED = 18;
int YLED = 19;
int RLED = 23;
int BLED = 21;
int PLED = 22;
const char* ssid = "Wokwi-GUEST";
const char* password = "";

const char* hostname = "broker.hivemq.com";

WiFiClient espClient;
PubSubClient client(espClient);
const char* espClientName = "esp32Client_S10257172B"; // yourStudentID must be unique
int PORTNUM = 1883;
int ledState = LOW; // ledState used to set the LED
long previousMillis = 0; // will store last time LED
int interval = 1000; // interval at which to blink (milliseconds)
int ledState2 = LOW;  

void setup_wifi()
{
  WiFi.begin(ssid, password);
  while(WiFi.status() != WL_CONNECTED )
  {
    delay(1000);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("Given IP by the router to ESP32 is ");
  Serial.println(WiFi.localIP());
}

void setup_MQTT(){
  client.setServer(hostname, PORTNUM);
  client.setCallback(callback);
}
void connectMQTT()
{
  while(!client.connected() )
  {
    Serial.println("Connecting to MQTT ...");
    if (client.connect(espClientName) ) //, mqttUser, mqttPassword) )
    {
      Serial.println("Connected");
      MQTTSubscribe();
    }
    else
    {
      Serial.print("Failed with state ");
      Serial.print(client.state() );
      delay(2000);
    }
  }
}

void callback(String topic, byte* payload, unsigned int length)
{
  String messageTemp;
  Serial.print("Message received in topic: ");
  Serial.print(topic);
  Serial.print(" length is: ");
  Serial.println(length);

  Serial.print("Data received from broker: ");
  for (int i = 0; i<length; i++)
  {
    Serial.print( (char)payload[i] );
    messageTemp += (char)payload[i];
  }

/// Handle your topics and payload here
// Example

  if (topic == "lsk/room/LED")
  {
    Serial.print("Changing water valve to ");
    if (messageTemp == "Close")
    {
      digitalWrite(PLED, HIGH);
      Serial.print("Close ");
    }
    else if (messageTemp == "Open")
    {
      digitalWrite(PLED, LOW);
      Serial.print("Open ");
    }
  }
  
  
}

void MQTTSubscribe() //if not subscribed led will not turn on or off
{
  // Subsccribe to your topics here
  client.subscribe("lsk/room/LED");
  client.subscribe("sk2/room/LED");  
  client.subscribe("pHsensor1Green");
  client.subscribe("pHsensor1Yellow");
  client.subscribe("pHsensor1Red");
}



void setup() 
{
  Serial.begin(9600);
  delay(5000);

  pinMode(GLED, OUTPUT);
  digitalWrite(GLED, LOW);

  pinMode(YLED, OUTPUT);
  digitalWrite(YLED, LOW);

  pinMode(RLED, OUTPUT);
  digitalWrite(RLED,LOW);

  pinMode(BLED, OUTPUT);
  digitalWrite(BLED,LOW);

  pinMode(PLED, OUTPUT);
  digitalWrite(PLED,LOW);

  pinMode(33, INPUT);
  pinMode(32, INPUT);
  
  setup_wifi();
  setup_MQTT();
}






void loop() 
{
  if ( !client.connected() )
  {
    connectMQTT();
  }
  client.loop();
  int adcRes = analogRead(A4);
  Serial.println("The digital value");
  Serial.println(adcRes);
  delay(500);

  float voltage = adcRes * 3.3/4095;
  Serial.println("The voltage value ");
  Serial.println(voltage);
  long currentMillis = millis();
  if(currentMillis - previousMillis >= interval)
  {
    previousMillis = currentMillis; // save the last time you blinked the LED
    if (ledState == LOW)
    {
      ledState = HIGH;
      client.publish("lsk/room/LED","Close");
    }
    else
    {
      ledState = LOW;
      client.publish("lsk/room/LED","Open");
    }
  }
  if(adcRes>=1000)
  {
    digitalWrite(21,LOW);
    client.publish("sk2/room/LED","On");
  }
  else
  {
    digitalWrite(21,HIGH);
    client.publish("sk2/room/LED","Off");
  }
  int adcRes1 = analogRead(A5);
  Serial.println("The digital value");
  Serial.println(adcRes1);
  delay(500);

  float voltage1 = adcRes1 * 3.3/4095;
  Serial.println("The voltage value ");
  Serial.println(voltage1);

  float pH = (-5.6548*voltage1)+15.509;
 Serial.println("pH Value is");
 Serial.println(pH);
  
  if(pH >5.8 && pH <=6.5)
  {
    digitalWrite(18,LOW);
    client.publish("pHsensor1Green","On");
  }
  else
  {
    digitalWrite(18,HIGH);
    client.publish("pHsensor1Green","Off");
  }


 if ((pH >= 5.5 && pH <= 5.8) || (pH >= 6.5 && pH <= 6.8))
    {
    digitalWrite(19, LOW);
    client.publish("pHsensor1Yellow", "On");
  } 
  else 
   {
    digitalWrite(19, HIGH);
    client.publish("pHsensor1Yellow", "Off");
  }

  if(pH <5.5 || pH >=6.8)
  {
    digitalWrite(23,LOW);
    client.publish("pHsensor1Red","On");
  }
  else
  {
    digitalWrite(23,HIGH);
    client.publish("pHsensor1Red","Off");
  }

  
}